Half-life (abbreviated t 1⁄2) is the time required for a quantity to reduce to half its initial value. The term is commonly used in nuclear physics to describe how. half-life [haf´līf″] the time required for the decay of half of a sample of particles of a radionuclide or elementary particle; see also radioactivity. Symbol t½. Browse and play mods created for Half-Life at Mod DB. Half-Life (stylized as HλLF-LIFE) is a science fiction first-person shooter video game developed by Valve, released in 1998 by Sierra Studios for Microsoft Windows. Half-Life, stylized as HλLF-LIFE, is a science fiction first-person shooter developed and published by Valve. The player takes the perspective of scientist Gordon. Half life was the first FPS game that I played and it means a lot to me. I've played many first person shooters but nothing comes close to this one. IGN is the Half-Life 3 (PC) resource with reviews, wikis, videos, trailers, screenshots, cheats, walkthroughs, previews, news and release dates Half-Life 2, free and safe download. Half-Life 2 latest version: This adventure is not going to be easy.expect anything. Find info about the game, click on thumbnails to open full screenshots, or watch the trailer. Fan-made Half-Life 3 logo, based on official shirt as seen below. Since the release of Half-Life 2: Episode Two in October 2007, there has been very little news from.